Device for the fast pricking out of plants

ABSTRACT

The present invention relates to a device for rapidly pricking out plants. It is comprised of a positioning element comprising an internal vertical passage wherein the plant together with its ball of earth, introduced through the top or through the bottom, may be immobilized momentarily by appropriate device, before it is driven from top to bottom towards the planting area by use of rods penetrating sideways into the positioning device through slots provide to this effect so as to bear directly to the earth ball without touching the foliage. It relates to the industrial field of agriculture machines and is intended to the automatic high speed transfer of earth ball-borne plantlets.

The subject of the present invention is a device for quickly prickingout plants.

It relates to the industrial field of agricultural machinery, and isintended for the high-speed automatic transfer of very young plants withroot balls.

In the devices for automatic pricking-out which are known to date, theroot ball together with the seedling which is to be pricked out isgenerally introduced from above into a positioning element the purposeof which is either to convey the plant above the place where it is to beplanted, or to hold it temporarily in order to allow a conveyor systemto convey the planting zone under the seedling which is then ejectedfrom the positioner element by a mechanical, pneumatic or some othermeans into a cavity or pre-hole prepared beforehand for this purpose.

For example, Patent No. FR 90 05172, by the same inventor, describessuch a device which consists of a vertical positioner into which theyoung plant is introduced simply under gravity, and of a blowing headwhich fits over the positioning element and allows air or gas to beinjected into it when the assembly comes above the pricking-out place.With this system, it sometimes happens that the seedling falls downbeside the positioner or topples over, which as often as not means ithas to be removed.

This method exhibits the additional drawback of causing a substantialamount of time to be wasted. This is because before it is possible toreach the final phase of pricking-out, it will have been necessary toextract the plant using means which as often as not present risks ofmutilating the leafy or root part and to transport it to its finalplace.

Another patent filed, still by the same applicant, under No. FR 91 13350describes an opening vertical positioning element formed of two partsseparated by an axial vertical seedling which can move away from eachother, said positioner being associated, on the one hand, with avertical push rod which can introduce into it from below the young plantwith its root ball when it is open, appropriate automatic means thencausing it to close so as to hold onto the seedling and, on the otherhand, with a mechanical ejector which drives the plant downward into theplanting zone by pressing on the root ball by means of rods the ends ofwhich have a bulbous portion.

In service, this second system has revealed a significant shortcoming.As they move vertically downward, the rods of the ejector beforereaching the root ball brush against the leafy part, which is oftendamaged.

The device according to the present invention, which may be consideredas an improvement to Patent No. FR 91 13350, has as its objective toovercome these drawbacks. It actually makes it possible to avoid anywaste by eliminating any risk of mutilating the leafy part, whileproviding a very high rate of pricking out.

It consists of a positioning element including a vertical internalpassage in which the seedling with its root ball, introduced from aboveor from below, can be temporarily immobilized by appropriate meansbefore it is driven out downward toward the planting zone by virtue ofrods penetrating the positioner laterally via slots provided for thispurpose so that they press directly on the root ball without touchingthe leafy part of the seedling.

In the attached diagrammatic drawings, given by way of nonlimitingexamples of embodiments of the subject-matter of the invention:

FIG. 1 represents, in perspective, a conically tapered positionerassociated with an upper ejector with a vertical movement provided witha sliding sleeve intended to bring the rods closer together when theirends are even with the upper part of the root ball,

FIGS. 2 and 3 show, in vertical axial section, the same positioner withthe rods in the up and in the down position respectively,

FIG. 4 represents, in elevation, a cylindrical positioner with a movingelement for immobilization, with lateral ejector with pivoting movement,

FIG. 5 is a transverse section on arrows A--A of FIG. 4,

FIG. 6 represents, in elevation, a positioner with a mobile element forimmobilization, with sliding lateral ejector integral with this mobileelement,

FIG. 7 is a transverse section on arrows B--B of FIG. 6

And FIG. 8 shows, viewed from above, the arrangement of multiplepositioners in a staggered configuration.

The device, FIGS. 1 to 7, consists of an assembly formed of apositioning element 1, 11 with a vertical internal passage for theseedling 2, and of an upper mechanical ejector 3, or lateral mechanicalejector 13 bearing flexible or rigid rods 4, 14 arranged to penetratethe positioner laterally through slots or openings 5, 15 provided forthis purpose and to drive the seedling downward by pressing on the rootball 6 without touching the leafy part 7.

In a first embodiment (FIGS. 1 to 3), the internal passage of thepositioner 1 is, in succession, conically tapered at the top andcylindrical at the bottom, the lower cylindrical part having a diameterwhich is slightly smaller than that of the root ball 6 so that theseedling 2 is held inside the positioner.

Above the latter there is an ejector 3 with a vertical movement extendeddownward by at least two flexible rods 4 which are curved so that theyare distant from the leafy part 7 of the seedling when their ends areresting on the root ball 6.

The rods 4 may also either be formed of flexible wires or strips, whichmay or may not be made of metal, or be rigid and articulated or fixed tothe ejector by a spring 8 or some other elastic element providing themwith their flexibility (FIG. 3).

The seedling 2 is introduced either from above or from below thepositioner 1. In the second case, said positioner consists of at leasttwo moving parts which can move far enough from each other to allow thepassage of the plant with its root ball. When the plant has reached itsposition, a mechanism causes the moving parts to move closer together soas to hold the seedling inside the positioner, by virtue of itssmaller-diameter lower cylindrical part. The positioning element 1 maybe opened by the horizontal sliding of the moving parts, or by virtue ofan articulation system with twin stays, or by a vertical-axis hinge, orby any appropriate means.

When the seedling 2 is in place in the positioner 1, the ejector 3 islowered until the ends of the rods 4 are just above the root ball 6.Said rods which, at rest, are separated so as to be distant from theleafy part 7 and make it easier for the seedling 2 to be introduced, arethen brought closer together so that they pass through the slots 5, byvirtue of the action of a cylindrical sleeve 9 sliding vertically aroundthe upper part of the rods, downward, in order to move the rods tightertogether, and upward for releasing them. Finally, the ejector 3 islowered again in order to drive the seedling out toward the plantingzone, forcing it through the cylindrical part of the positioner.

In a second embodiment (FIGS. 4 and 5) the internal passage of thepositioner 11 has the shape of a U-shaped channel section closed by anarticulated part 12 arranged so that by virtue of a spring it presses onthe seedling 2 in order to immobilize it after it has been introducedinto the inside of the positioner. An adjustable stop 16 prevents saidarticulated part from closing up again on the leafy part 7 when the rootball 6 is pushed out of the device, while allowing this device to beused for seedlings of various sizes. A rotary device, such as a cam, arotary shaft 17 which may be square or have a variable profile, or someequivalent means moves the channel section and the articulated part 12apart when the plant is introduced.

During the pricking-out phase, the plant is driven toward the plantingzone by means of a lateral ejector 13 with a movement which pivots aboutan axis, and which is extended by two rods 14 arranged to pass throughslots 15 formed between the U-shaped part of the positioner 11 and thearticulated part 12, during this operation, the channel section is keptin a vertical position by virtue of a retractable stop 18. The positionof the axis of the ejector 13 and the length of the rods 14 aredetermined so that the ends of these rods can press against the rootball 6 without the risk of damaging the leafy part 7.

Just as with the conically tapered positioner 1, said rods may beflexible, initially apart so as to pass on each side of the articulatedpart 12, penetrating the positioner 11, and brought closer together inthe down position (in dotted line, reference 14' in FIG. 5) thusrecentering the seedling 2, by virtue of the action of a cylindricalsleeve 9 or similar device sliding axially along the ejector 13.

According to an alternative embodiment (FIGS. 6 and 7), the seedling 2is driven out toward the planting zone by means of a lateral ejector 13'with a vertical sliding movement integral with the articulated part 12.

The ejector 13' is formed of a vertical rod 20 sliding in a support 21fixed to the articulated part 12. The vertical rod 20 is terminated atits upper end by a fitting 22 with a rounded head or bearing a roller,and at its lower part bears two rods 14' arranged to pass through theslots 15 formed between the U-shaped part of the positioner 11 and thearticulated part 12. A return means 23, such as a spring slipped overthe vertical rod between the support 21 and the fitting 22 keeps saidrod in the up position at rest. The downward movement of the verticalrod is brought about by a cam 24, a push rod or a lever acting on thefitting 22.

The rods 14' may be flexible, initially apart so as to pass each side ofthe articulated part 12, penetrating inside the positioner 11, andbrought closer together in the down position (in dotted line, reference14' in FIG. 7) thus recentering the seedling 2, by virtue of a U-shapedpart in the form of a cone.

Several positioning elements 1, 11 operating simultaneously mayadvantageously be arranged in a row.

In particular, it is possible to combine several parallel sets 25 on oneand the same supporting structure, the positioning elements of one setbeing arranged in a staggered configuration with respect to thepositioning elements of the contiguous sets. The sets, which operatesimultaneously or alternately, deposit the seedlings on successivestaggered rows of the same planting zone, but are fed by transfersystems 26 from two loading boxes or trays 27, 28 arranged on each sideof the series of sets 25, so as to allow these to operate without movingsideways. The two loading trays 27, 28 each have a different number ofcells in the lengthwise direction, and preferably move in oppositedirections. This particular feature considerably simplifies theconstruction and development of high-rate pricking-out machines, whilegiving them a remarkable reliability.

The positioning of the various constituent elements gives thesubject-matter of the invention a maximum useful effect which has nothitherto been obtained with similar devices.

I claim:
 1. A device for pricking out a seedling having a root ball anda leafy part, comprising:a positioning element including a channelsection with an articulated part delimiting a passage for the seedling,the channel section having an open side partially closed by thearticulated part except for two elongated openings located on both sidesof the articulated part, the articulated part being movable away fromthe channel section to allow an introduction of the seedling, thearticulated part pressing the seedling against the channel section toimmobilize said seedling; and a mechanical ejector having two movablerods capable of penetrating inside the passage of the positioningelement by sliding respectively through the elongated openings to applya pressure on the root ball without damaging the leafy part and drivethe seedling toward a planting zone.
 2. The device as claimed in claim1,wherein the positioning element further comprises:a spring to hold thearticulated part against the seedling; and an adjustable stop to preventthe articulated part from closing onto the leafy part when the root ballis driven out of the positioning element, while allowing the latter tobe used for seedlings of various sizes.
 3. The device as claimed inclaim 2,wherein the positioning element comprises a rotary element witha variable profile to move apart the channel section and the articulatedpart during the introduction of the seedling.
 4. The device as claimedin claim 3,wherein the rotary element is a cam.
 5. The device as claimedin claim 3,wherein the rotary element is a rotary shaft with a squarecross section.
 6. The device as claimed claim 1, further comprising aretractable stop to keep the channel section in a vertical positionduring a pricking out phase.
 7. The device as claimed in claim 6,whereinthe positioning element has a U-shaped part delimiting the passage withthe articulated part, and wherein the mechanical ejector comprises:asupport fixed to the articulated part; and a vertical shaft capable ofbeing slid in the support, the vertical shaft having an upper endterminated by a fitting with a rounded head; and wherein the devicefurther comprises:a cam for pushing downwardly the vertical shaft byapplying a vertical pressure onto the rounded head, the shaft beingreturned to an upper position of rest by a resilient means, the shafthaving a lower part to bear the two movable rods which are arranged toslide through the elongated openings, and the elongated openings beingformed between the U-shaped part and the articulated part.
 8. The deviceas claimed in claim 7,wherein the resilient means is a spring mountedaround the vertical shaft between the support and the fitting.
 9. Thedevice as claimed in claim 1,wherein the mechanical ejector bearing thetwo rods is capable of a pivotal movement about an axis, said axishaving a position and the rods having a length determined so that endsof these rods apply the pressure on the root ball without damaging theleafy part.
 10. The device as claimed in claim 9,wherein the mechanicalejector comprises a cylindrical sleeve capable of being slid axiallyalong the rods, and the rods are flexible, initially apart so as toslide through the elongated openings when the sleeve is not slid alongthe rods, penetrating inside the passage then brought closer together ina down position when the cylindrical sleeve is slid axially along therods.
 11. Arrangement of devices as claimed in claim 1, 3, 4, 7 or 8,comprising several parallel sets, each including several of thepositioning elements, the sets being mounted on a single supportingstructure, the positioning elements of each set being arranged, inseries, in a staggered configuration with respect to the positioningelements of contiguous sets, the arrangement also comprising two loadingtrays for feeding the sets, the trays being arranged on each side of theseries of sets so as to allow these to operate without moving sideways.12. Arrangement of devices as claimed in claim 11,wherein the twoloading trays each has a different number of cells in a lengthwisedirection, and move in opposite directions.